We choose a highly conserved, 21 nucleotides long RNA sequence of the HIV1 LTR repeat which could serve as a potential target for drug design. Selective blocking of this sequence by a complementary binding chemical compound could inhibit or stop the viral reverse transcription machinery. So far phase sensitive NOESY and TOCSY spectra at 600 Mhz have been performed, allowing a complete assignment of the 21mer hairpin. In order to prevent molecular aggregation, all experiments have to be carried out at 1 mM sample concentration. For some crucial resonances, the integration of NOESY crosspeaks is difficult due to a low signal/noise. We expect from the future NOESY/ROESY measurements at 750Mhz a 2-fold higher signal/noise, thus allowing the unambiguous integration of more reliable and significant NOEs and ROEs which would help us in defining a more rigid and unitary molecular geometry.